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Date: Sat, 26 Nov 2005 21:28:12 +0100
From: Herve Boulouis <amon@sockar.homeip.net>
To: user <user@dhp.com>
Message-ID: <20051126202812.GB594@ra.aabs>
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Cc: freebsd-scsi@freebsd.org
Subject: Re: configuration choices with Dell CERC (adaptec 2610SA)
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Le 26/11/2005  15:22, user a écrit:
> 
> One other clarification - I have the option to turn write caching on and
> off when I create the array (I am turning it ON now for the array based on
> your opinion) ... but I also have an option in the adaptec bios to turn
> write-caching on for each specific disk drive.  I have also turned this
> on.
>
> caching for the array _depend on_ having write caching for each drive
> turned on ?)

Never enable the disk write caching. The raid controller write caching
is safe if you have a battery on the card or a UPS whereas the disk write
cache can never be safe.

-- 
Herve Boulouis